The present invention relates to adjustable closures used to dispense particulate and powdered materials from containers, and in particular, to a multi-functional, environmentally-oriented, tamper-evident container closure which may be removably attached to a container end.
Containers are known for particulate and powdered products, such as grated cheese products, seasonings, and non-dairy creamers, which include adjustable plastic closures for dispensing the product by pouring or shaking the container. Such closures have a post-mounted, plastic rotor portion fastened to 15 an assembly or plastic container end. See for example, van Kerkhoven, et al, U.S. Pat. No. 4,969,572; Weidman, U.S. Pat. No. 4,792,054; Kacalieff, U.S. Pat. No. 4,611,725; Davis, U.S. Pat. No. 4,480,864; Otterson, U.S. Pat. No. 4,308,979; Weatherhead, III, U.S. Pat. No. 3,874,580; and LaCroce, U.S. Pat. No. 3,486,665.
The '864 patent to Davis also discloses a punch-out closure comprising a one-piece plastic cap with a punch-out tab, and a post-mounted plastic rotor attached to the cap to cover or expose the opening which is formed by the punch-out tab.
Other features are shown in containers for particulate and powdered products. Plastic lids having a peripheral locking rib attached to a container having a separate container end are shown by Kreiseder et al, U.S. Pat. No. 4,598,837 and Hougen et al, U.S. Pat. No. 3,826,400. In the '837 patent to Kreiseder et al, the plastic lid is also attached to the plastic container end by a post. In the '400 patent to Hougen et al, the plastic lid is removably attached by the peripheral ribs to a metal container end which includes a break-away portion in the form of a pull tab. The plastic lid serves to prevent accidental and premature lifting of the pull tab which would break the seal, and expose the beverage contents to spillage and contamination.
Metal container ends having easy-open push-in portions are also known, and are widely used for dispensing liquids. See for example, Madden et al, U.S. Pat. No. 4,196,823; Debenham et al, U.S. Pat. No. 4,155,480; Gane, U.S. Pat. No. 4,128,186; and Elser, U.S. Pat. No. 4,126,244. However, such push-in metal ends have, heretofore, not been used with plastic lids to produce significant additional function in cooperation therewith.
The use of multi-material containers, and non-biodegradable materials is growing in disfavor as the environmental movement expands, and landfills fill up. Legislation is pending or has obtained passage in a number of states limiting container construction to two biodegradable materials. Such changes promise to impose burdens on manufacturing facilities which currently produce disfavored, multi-material containers. Accordingly, the need exists for improved container designs to meet the needs of consumers for easy access, convenience, and safety, while satisfying the increasing demands for environmentally acceptable disposal.